Early cellular telephones typically had a two-piece design which included a cradle and a handset connected to the cradle. Most of the electronics of these early cellular telephones was disposed in the cradle.
As cellular telephones developed over the years, their size has steadily decreased. This has been partly due to the integration of many of the telephones electronic functions into semiconductor devices such as digital signal processors specifically designed to process the electrical operations of a cellular telephone. In addition, smaller, more powerful batteries have been developed. This has allowed cellular telephone makers to adopt one piece designs. In these one piece designs, all of the functions of the handset and the housing are integrated into a one-piece hand held unit.
Cellular telephones are typically used extensively within vehicles such as cars and trucks. Cradles for newer one-piece telephones typically attach to the vehicle and provide a secure receptacle to hold the telephone when it is not in use. Because all of the functions are integrated into the telephone itself, there are no electronic components disposed within the cradle. Furthermore, there is typically no electrical connection between the cradle and the telephone as was required with older two piece designs.
Prior art cradles typically include latching mechanisms in order to hold the telephone securely in the cradle. The latching mechanism holds the telephone tightly in place, thereby assuring that the telephone will not fall out of the cradle. In order to use the telephone while in the vehicle, the telephone must first be removed from the cradle. However, prior art cradles typically include one or more buttons which must be pressed in order to release the telephone. Thus, in order to remove the telephone from the cradle, the user must press the buttons and lift the telephone out of the cradle. These buttons are relatively small and are located on opposite sides of the cradle. This requires two hands, one hand to press the two buttons and one hand to lift up the telephone. In addition, the user must look down to see the location of the two buttons in order to press them.
After pressing the buttons, the user must then lift the telephone out of the cradle to operate the telephone. This is difficult and time consuming, particularly when the phone is ringing and the user is busy operating the vehicle. This makes removal of the telephone difficult if not impossible while the user is operating the vehicle.
The telephone must then be operated. Recent telephone designs have included smaller and smaller telephones. These recent telephone designs have small keyboards which include one or more function keys and small displays. When an incoming call is received, the cellular telephone typically makes a ringing sound. The user typically establishes a cellular connection by pressing one or more function keys while the telephone is ringing. These keys are typically quite small and are difficult to operate quickly without excessive distraction. The telephone must then be placed up to the user's face such that the microphone is near the user's mouth and the speaker is near the user's ear. This requires the user to use one hand to operate the telephone for the duration of the cellular connection. This can be a problem when the user needs both hands. For example, when a user is driving around a corner, he must either turn one-handed which is dangerous or set the phone down.
Recently, some car manufacturers have developed integrated systems which include a microphone attached to the roof of the car. Such systems also deliver the audio portion of the telephone through the speakers of the car stereo system. Because the speakers are typically not close to the driver, road noise and other sounds interfere with the driver's ability to hear the sounds transmitted over the cellular telephone.
In many of these integrated systems, the user must still look down to find the telephone and turn it on. Because the microphone is placed in the roof, the microphone picks up noise from the vibration of the vehicle. Moreover, in many instances, the microphone is not close to the user. This gives poor reception. Because such integrated systems are only compatible with certain types of telephones, the user is required to purchase a compatible telephone. This can be quite expensive, particularly when the user already has a portable cellular telephone, because the user must purchase a second telephone for the vehicle. In addition, because these systems are built into the vehicle, they are typically quite expensive.
Users who operate in different vehicles are also disadvantaged by such integrated systems because they cannot readily move the system from one vehicle to another. Thus, a separate system must be installed in each vehicle.
What is needed is a microphone and speaker system which is easy to operate and which does not interfere with the driver's operation of the vehicle. In particular, a microphone which is conveniently located and which achieves good reception is needed. In addition, a speaker unit which is close to the driver and which delivers quality sound to the user is required. Moreover, a system which is easy to turn on and off is required. Additionally, a system which may be moved from one vehicle to another is needed.